Method of and apparatus for removing slip sheets



May 29, 1934.

P. C. TRAVER METHOD OF AND APPARATUS FOR REMOVING SLIP SHEETS Filed NOV. 1929 Patented May 29, 1934 METHOD OFAND APPARATUS FOR REMOV- ING SLIP SHEETS Paul C. Traver, Chicago, Ill., assignor to Traver Paper & Manufacturing 00., Chicago, 111., a corporation of Illinois Application November 1, 1929, Serial No. 404,674

4 Claims.

This invention relates to improvements in method of and apparatus for removing slip sheets and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

In the printing art, it is sometimes necessary to interleave between freshly printed sheets, other blank sheets termed slip sheets to prevent offsetting of the printed sheets from one to the other when arranged with the desired number of interleaved sheets in a stack. After the printed sheets have dried, it is necessary to remove the slip sheets therefrom. This removing of the slip sheets as now practiced is a slow, tedicus, and laborious task and materially increases production costs.

The primary object of the invention is to provide an improved method of removing slip sheets which method increases production and reduces costs, which does not require that amount of effort as will produce fatigue and which does not result in such waste as heretofore due to tearing the printed sheets when pulling the slip sheets.

Another object of the invention is to provide a simple and efficient apparatus whereby the method may be more expeditiously carried out.

These objects of the invention as well as others, together with the many advantages thereof, will more fully appear as I proceed with my specification.

In the drawing:--

Fig. 1 is a view in side elevation of an apparatus whereby my improved method of removing slip sheets may be expeditiously carried out.

Fig. 2 is a fragmentary top plan View of one end corner of the apparatus shown in Fig. 1.

Fig. 3 is a detail vertical sectional view as taken on the line 3-3 of Fig. 1.

Fig. 4 is a view in side elevation of a stack or plurality of interleaved printed and slip sheets with which my invention is particularly con-, cerned and which will be more fully referred to later.

Referring now in detail to the structure of the apparatus shown in Figs. 1 to 3 inclusive of the drawing, 1 indicates as a whole a horizontally disposed, rectangular table top or support mounted at its corners upon upright front and rear legs 2 and 3 respectively, the rear legs being suitably braced from the table top or support as by the angularly disposed brace members 4. At each side of the table top or support, above the rear legs 3 are bearing blocks 5 in which a transversely extending, horizontally disposed shaft 6 is journalled for a rocking movement. In said shaft is provided a longitudinal key-way or groove 7. Fixed to said shaft between the bearing blocks 5 is a plurality of forwardly extending arms 8 only one of which is shown in Figs. 1 and 2. This arm includes a hub 9 to receive the shaft and said hub carries a setscrew 10 to engage the groove 7 whereby the arm may be adjusted longitudinally of the shaft into the desired position thereon.

The forward or free end of each arm carries an adjustable member 11 having a yielding presser foot 12 which in this instance is a rubber button. 13 indicates an edgewise disposed guide or stop bar which extends transversely of but in engagement with the table top or support in a plane between those of the presser feet 12 and the bearing blocks 5. Preferably said stop bar is adjustable toward and away from said bearing blocks. To permit of such adjustability I provide the guide bar at each end with a guide rod 14 that extends through a suitable opening in the associated bearing block and a setscrew 15 is threaded into each bearing block in a manner to engage each rod 14 and lock the guide bar in the desired position.

On one end (preferably the right hand end) of the shaft 6 and outside of the adjacent bearing block 5 is fixed a rearwardly extending arm 16 and below said arm as well as below the table top or support is located a lever 17 whereby said arm 16 is actuated. The lever 17 is pivoted as at 18 to the brace 4 and its front end 17 extends forwardly beyond the front end of the table top or support into a position to be conveniently grasped by the operator. On the associated front leg 2 is provided a downwardly facing hook or latch 18 under which the said end of the lever may be engaged to be held thereby. The rear or short arm 17* is yieldingly connected to the arm 16 by means of an expansion spring 19. Said spring engages at one end upon said arm 17 and engages at its other end with a link 20 which is pivoted to the arm 16 as at 21. A tube 22 surrounds the spring to prevent its displacement and this tube is pivoted at one end as at 23 to said link and has a pin and slot connection at its other end with said lever arm 17 As before stated when the sheets being printed are of such character that they will not immediately absorb the printing ink impressed upon them, it is necessary to interleave other sheets therebetween to prevent offsetting from one to the other of the printed sheets. As a material which requires such interleaving of slip sheets therebetween during the printing thereof, I mention glassine paper, cellophane, and the like. When printing upon cellophane, as by means of a rotary cylinder press, the supply is drawn from a roll and in connection therewith is provided a roll of slip paper. The two rolls are laterally offset in the press and after the cellophane is printed, both webs are out transversely into sheets which are arranged the desired number of interleaved sheets in a stack. This brings the marginal portions of the printed sheets at one end of the stack beyond the marginal portions of the slip sheets at said end of the stack and, of course, brings the marginal portions of the slip sheets at the other end of the stack beyond the associated ends of the printed sheets.

In Fig. 4 I have illustrated such a stack of printed and interleaved slip sheets 25 and 26 respectively wherein it will be noticed that the said sheets are offset so that marginal portions 25 of the printed sheets are arranged at one end (the right hand end) of the stack and the marginal portions 26* of the slip sheets are arranged at the other end (the left hand end) of the stack.

I take such a stack of interleaved printed and slip sheets and place them in an orderly manner upon the table 1 of my improved apparatus before described with the end edges of the margins 25 engaged against the guide bar 13. Before so placing the stack upon the table, I release the lever end 1'7 from the hook 18 so that the presser feet 12 may be elevated into a position above the table. However, after the stack has been placed upon the table, as mentioned, a downward pressure is imposed upon the lever end which is then engaged under the hook 18 When the lever is thus secured in place, it is apparent that the spring 19 will exert an upward thrust on the arm 16 which will tend to so rock the shaft 5 as to bring the presser feet 12 into engagement with the margins 25* of the printed sheets as best shown in Fig. 1 so as to hold said printed sheets in place.

To break any adhesive bond or suction between the sheets, they may be rolled up from the free end of the stack and then unrolled so as to again lay fiat upon the table. Thereafter the operator grasps the margins 26 of several of the slip sheets and pulls thereupon to withdraw them from the stack without disturbing the printed sheets which are still held in place by reason of the engagement of the presser feet 12 with the margins 25 of said sheets.

This operation is repeated until all the slip sheets are removed from the stack leaving only the printed sheets therein. The lever arm 17* is again released from the hook 18 and this removes the presser feet from the printed sheets which can now be removed from the table as an orderly stack ready for packing for shipment.

Thereafter another stack of interleaved sheets is placed upon the table 1 and the slip sheetsare pulled or removed from said stack as before described.

hee ess By the improved method described, the slip sheets may be quickly removed and this without waste due to tearing of the printed sheets. The method has increased. the number of slip sheets that can be pulled in a given time and this with less operators than heretofore.

- The method represents a substantial saving in establishments doing Work requiring the pulling of slip sheets and the apparatus by which the method is most expeditiously carried out is simple in construction and has no parts which can readily get out of order.

In describing the invention, I have referred in detail to the form, arrangement and construction of the various parts of the apparatus as well as the various steps in the improved method, the same is to be considered merely as illustrative so that I do not wish to be limited thereto except as may be pointed out in the appended claims.

I claim as my invention:

1. An apparatus of the kind described embodying therein a support, a sheet edge guide on said support, presser foot members mounted above the support in advance of said guide, a lever and means between said lever and presser foot members for yieldingly urging said presser foot members toward said support when said lever is in a predetermined position, said lever being movable into a second position for moving said presser members away from said support.

2. An apparatus of the kind described embodying therein a support, a sheet edge guide on said support, a rock shaft on said support to one side of said guide, arms fixed to said shaft and each carrying a presser foot arranged to the other side of said guide, a power arm fixed to said shaft, a lever, means between said lever and arm including a yielding device for actuating said power arm to rock said shaft in one direction.

3. An apparatus of the kind described embody- 11 ing therein a support, a sheet edge guide on said support,-a rock shaft on said support, arms fixed to said shaft and each carrying a presser foot, a power arm fixed to said shaft, a tube pivoted to said arm, a lever having a pin and slot connection with one end of said tube and yielding means between said lever and the other end of the tube for rocking said shaft in one direction.

4. The method of removing desired sheets from a stack of interleaved, individual, alternate and intermediate sheets arranged with like margins of the alternate sheets projecting from associated margins of the intermediate sheets at one end of the stack and which method consists in holding the projecting margins of the alternate sheets together against relative movement of said sheets, operating upon said stack of sheets to break any bond between the engaging parts of said alternate and intermediate sheets and then exerting a pull upon another margin of the intermediate sheets to remove them from between the alternate sheets of the stack.

PAUL C. TRAVER. 

